Benita Refson, chief executive of Charity Award-winning Place2Be celebrated on behalf of her charity: “This is a tremendous endorsement of the tireless work and commitment of our staff, volunteer counsellors and supporters.”

She added: “By helping to raise awareness of the Place2Be’s early intervention work in schools, the Duchess will also help the charity to reach even more to the UK’s most vulnerable children.”

SportsAid chief executive Tim Lawler also welcomed the announcement and said: “I can think of no greater endorsement for SportsAid than for me to be able to welcome Her Royal Highness the Duchess of Cambridge as the charity’s patron.”

The Duchess opened the Natural History Museum’s Treasures exhibition last year, director of the museum Dr Michael Dixon said: “When she was here last November it was clear to me how much she shares our passion for understanding and maintaining the diversity of our planet. I very much look forward to involving her more in our work and hope she may join us in inspiring the next generation.”

All three charities will now be invited to join the Prince's Charities Forum, an initiative started by the Duke of Cambridge and Prince Harry in 2006 to bring together their charitable interests.